I'd say your computer screen is the problem and/or the software you're using to view them. I've got a wide gamut IPS panel monitor that gets calibrated every month to ensure consistent colour. The software you use, including your internet browser can do funky things to colours also. Are you shooting JPG files? Which colour space do you have it set to... sRGB or Adobe RGB? I'd suggest sRGB if you want your screen to match the camera better. Printing is a whole other ball game. You can see colour shift there too. What you WILL see on prints is that they appear darker than the photos did on screen. That's because monitors are back lit. Test printing can get around that though. I wouldn't suggest HDR for landscape as a rule, but there's certainly a place for it. Understanding what HDR is really achieving will show you why it can be of benefit and it's got nothing to do with that terrible over cooked look you'll see on a lot of shots. I'm not really a manual shooter myself. I'm happy to trust the camera's meter most of the time. Again, there's times where it's called for, but don't get caught up thinking manual is the holy grail.